21799678236 has 24 divisors (see below), whose sum is σ = 58132475520. Its totient is φ = 6228479472.

The previous prime is 21799678213. The next prime is 21799678249. The reversal of 21799678236 is 63287699712.

It is a self number, because there is not a number n which added to its sum of digits gives 21799678236.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 129759906 + ... + 129760073.

It is an arithmetic number, because the mean of its divisors is an integer number (2422186480).

Almost surely, 2^21799678236 is an apocalyptic number.

It is an amenable number.

21799678236 is an abundant number, since it is smaller than the sum of its proper divisors (36332797284).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21799678236 is a wasteful number, since it uses less digits than its factorization.

21799678236 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 259519993 (or 259519991 counting only the distinct ones).

The product of its digits is 13716864, while the sum is 60.

The spelling of 21799678236 in words is "twenty-one billion, seven hundred ninety-nine million, six hundred seventy-eight thousand, two hundred thirty-six".